/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.nifi.attribute.expression.language;

import org.apache.nifi.expression.AttributeValueDecorator;
import org.apache.nifi.parameter.Parameter;

public class ParameterExpression implements Expression {
    private final String parameterName;
    private final boolean allowSensitiveParameterReference;

    public ParameterExpression(final String parameterName, final boolean allowSensitiveParameterReference) {
        this.parameterName = parameterName;
        this.allowSensitiveParameterReference = allowSensitiveParameterReference;
    }

    @Override
    public String evaluate(final EvaluationContext evaluationContext, final AttributeValueDecorator decorator) {
        final Parameter parameter = evaluationContext.getParameter(parameterName);
        if (parameter == null) {
            return null;
        }

        if (!allowSensitiveParameterReference && parameter.getDescriptor().isSensitive()) {
            return null;
        }

        return parameter.getValue();
    }
}
